Meningitis is an inflammation of the membranes and fluid that surround the brain and spinal cord. There are two main types of the disease: viral meningitis, which can be caused by a number of different viruses, and bacterial meningitis, which results from a bacterial infection. There are both infectious (fungal and parasitic) and non-infectious causes. Early and accurate diagnosis is important so that an appropriate treatment course can be started as soon as possible.
Certain viruses, such as enteroviruses, influenza, and measles, can result in meningitis. Less commonly, a bacterial infection is a cause. The disease(s) are spread by respiratory secretions via sneezing, coughing, and kissing, but this rarely results in meningitis.
Infections that cause meningitis are contagious and typically spread by fluids that contain the infectious organisms. Sneezing, coughing, kissing, or even touching contaminated objects can spread the infection, but rarely result in meningitis.
Meningitis initially appears as a flu-like illness, with fever, headache, and sometimes a stiff neck. In the case of bacterial meningitis, the disease can become serious and even life-threatening in a matter of hours.
The meninges are composed of three layers of connective tissue—the pia, the arachnoid, and the dura layers—that protect the brain and spinal cord and the cerebrospinal fluid that flows around them. Meningitis is an inflammation of the meninges that is usually caused by an infection.
A clear, colorless fluid that surrounds the brain and spinal cord. To confirm a diagnosis of meningitis, a sample of CSF is withdrawn with a lumbar puncture (spinal tap), cultured, and examined under a microscope for bacteria or other signs of infection.
A vaccine used to provide protection against a relatively rare serogroup, or strain, of Neisseria meningitidis, a bacteria that can cause meningitis. The CDC does not consider this vaccine necessary for all teens (as with the MenACWY vaccine), but if it is given, the ideal age is between 16 and 18 years old.
The main vaccine used to provide protection against four serogroups, or strains, of Neisseria meningitidis, a bacteria that can cause meningitis; the serogroups are called A, C, W, and Y. The CDC recommends the MenACWY vaccine for all preteens and teens, with an initial dose at 11 to 12 years old, followed by a booster at age 16.
A diagnostic procedure, also called a lumbar puncture, in which a needle is inserted in between the bones of your lower back to withdraw a small amount of cerebrospinal fluid—the protective fluid that surrounds the brain and spine—so it can be studied more thoroughly in a lab. A spinal tap can confirm a diagnosis of meningitis.
Centers for Disease Control and Prevention. Viral meningitis. Updated August 6, 2019.
Centers for Disease Control and Prevention. Bacterial meningitis. Updated August 6, 2019.
Centers for Disease Control and Prevention. Meningitis. Updated January 21, 2020.
Centers for Disease Control and Prevention. Meningococcal disease. Updated June 7, 2017.
Centers for Disease Control and Prevention. Meningococcal vaccines for preteens and teens: Information for parents. Updated July 26, 2019.